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This is an excerpt from the latest version perlfaq4.pod, which
comes with the standard Perl distribution. These postings aim to
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4.27: How can I access or change N characters of a string?

You can access the first characters of a string with substr(). To get
the first character, for example, start at position 0 and grab the
string of length 1.

$string = "Just another Perl Hacker";
$first_char = substr( $string, 0, 1 ); # 'J'

To change part of a string, you can use the optional fourth argument
which is the replacement string.

substr( $string, 13, 4, "Perl 5.8.0" );

You can also use substr() as an lvalue.

substr( $string, 13, 4 ) = "Perl 5.8.0";



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